Concrete pipe, pole, column, and the like



y 23, 1933- J. H. SHERRARD 1,910,643

CONCRETE PIPE, POLE, COLUMN AND THE LIKE Filed Aug. 22, 1930 lib:

In van for J. S/irrard Patented Mayi2 3, 1933 UNITED STATES PATENTorrlcn 38H. ARI), OF WESTMOUNT, QUEBEC, CANADA GONGBETE PIPEP OLE,COLUMN, M D THE LIKE Application filed August 22, 1930. Serial No.477,081.

This invention relates broadly to improvements in pipes, columns, polesand like structures and to the process of making same, and relates moreparticularl to such structures composed of reinforce concrete or othermatter capable of hardening from an initial plastic condition, and therimary object of the invention is to provi e strong, durable andrelatively inex ensive structures as m aforesaid which may emanufactured easily and quicy. A. further object is to provide a novelform of reinforcement for concrete or similar structures of the typesmentioned which may easily, quickly and accurately set in place andwhich will afford a very secure bond for the concrete. A still furtherobject is to provide structures having great girder strength and capableof withstanding relatively high internal pressures. Various otherobjects and the advantages of the invention may be ascertained from thefollowing description and the accompanying drawmg.

According to the present invention, a thin 25 walled sheet metal tubularcore is pfirovided, the strength of the core being insu cient towithstand the stresses to which the finished structure will besubjected. The core is provided externally'or internally or both extermnally and internally with a layer of reinforcing fabric presenting amultitude of loops or links in which concrete or other material mayengage and thereby be connected to the core. The fabric is preferablycomposed of a series of interlinked helically formed rods or Wiresconnected at intervals to the core or entirely separate therefromaccording to circumstances. Additional non-helical reinforcingmembersmay be provided and connected as desired to the reinforcingfabric or to the core. The reinforced core may be lined or filled,according to the purpose of the structure, with concrete or othersuitable material and externally covered with concrete or other suitablematerial, the lining and covering being reinforced if desired.

The invention contemplates embodiment of the central idea and some orall of the details thereof in the manufacture of a vallll riety ofarticles such as beams, columns,

piles, pipes, poles and other similar structures but for brevit andfacility of explanation the following escription will be largelyconfined to the embodiment of the invention in the manufacture of pipes.

In the accompanying drawing which illustrates the chosen embodiment ofthe invention but to the details of which the invention is not confinedl Fig. 1 is a central longitudinal sectional view of a pipe constructedaccording to the invention.

Fig. 2 is a cross sectional view of the pipe shown in Figure 1.

. Fig. 3 is a fragmenta view of the core and rein orcing on largedscale.

cross sectional an en- Fig. 4 is a view similar to Figure 3 illustratinga slightly modified form of reinforc- 5 is a plan view of a fragment ofthe rein orcing fabric. Referring more particularly to the drawing, 11designates a tubular core preferably formed of relatively thin sheetmetal bent to the desired shape and having the edges thereof riveted,seamed or welded together. In the manufacture of pipes, it is preferredthe core should be fluid tight but this characteristic is not ofimportance in other structures. The stren h of the core is preferablyless than Wlll withstand the stresses which the finished structure isdesigned to withstand. By way of example, it may be stated it is nowpreferred to make the cores for ipes three to four feet in diameter outof s set metal approximately one-sixteenth 'of an inch thick but it willbe understood there; is no limitation to this thickness of metal ascores may be made of metal either thinner, or thicker for these sizes ofpipes ,as Well as for pipes of smaller and larger diameters. While thecore is, for pipes, preferably cylindrical, it will be understood thereis no limitation to this form, as other cross-sections may be adopted. I

The core is externally reinforced by a layer of metal fabric designated12. This fabric is composed of a series'of suitably hard helicallyformed rods or wires 13, the

' them, as shown in Figures 3, 4i and 5. In

helices of which are of any suitable pitch and are interlaced as clearlyshown in Figures 3 and 5. The fabric ma be preformed and applied to thecore as hereinafter described or may be formed upon the core. The fabricis preferably arranged with the axes of the helical members parallelwith the axis of the core. lit will be readily seen that in thisarrangement, the fabric is very flexible circumferentially of the core,so that it may be wrapped around the core substantially withoutresistance but is substantially inelastic circumferentially of the core,so that it may be heavily tensioned without causing material elongation.The low factor of elasticit; is due to t e fact that the interlinkedhelical members constitute in effeet a series of chains extendingcircumferentially of the core, as will be clearly seen from Figures 2, 3and 4:. Where it is desired to have the fabric in great tensioncircumferentially of the core, the helices ma be flattened as shown inFigure 4i. The e fect of tension in the fabric circumferentially of thecore is a tendency to reduce the pitch of the helices and in applyingthe abric to the core this tendency is resisted by lining the ends ofthe helical members to the ends of the core, so that no relief ofcircumferential tension will occur." The meet ing edges of the fabricmay be readily connected by interdigitating the helices of the two edgesand passing a rod 13 through addition to the fixing of the ends of eachhelical member to the ends of the core,-the fabric may be and preferablyis rigidly connected tothe core at a lurality of points in thecircumference and in the lengh of the structure by welding, brazing orother suitable means, so as to prevent the fabric moving locallyrelatively to the core. The fabric forms an excellent bond with concreteor other cementitious material by reason of the material on aging in themultitude of helices. When t e material is so engaged in the helices, itwill preventhattening of the same due to increase of tensioncircumferentially of the structure and will likewise prevent any changein the pitch of the helices which would relieve the tension.

The reinforced core is covered with a layer of cement concrete or othersuitable material 15 applied by moulding or plastering on and, ifnecessary or desired, consolidated b pressure or vibration applied inany suitab e way. This constitutes the rimary and most simp e form ofpipe accor ing to this invention.

If it is desired to impart reater girder strength to the pipe, longituinal reinforcing bars 16 may be provided outside the fabric 12 andwelded, brazed or tied thereto. Also, as alternative to the bars 15 oras additional thereto, longitudinal bars 17 may be threaded through thehelical members and welded or brazed to the core or to the helicalmembers or to both. The covering of concrete or other material may, ifdesired, be provided with reinforcing 18 embedded therein to retain thecovering in place in the event of fracture such as would otherwisepermit separation thereof from the reinforced core.

A layer of fabric 19 which may be and preferably is similar to the outerlayer 12 may be provided within the core 11. When the inner layer offabric 19 is of the type already described, it is preferred to arrangethe same so that the helically formed members 20 of which it is composedextend circumferentially of the core, i. e., at right angles to thesimilar members of the outer layer 12. In this disposition, each helicalmember is bent to the curvature or other form of the core and, by reasonof tendency to return to normal flat form, presses outwardly against theinner surface of the core. The inner layer of fabric may be connected tothe core at intervals in its length and circumference by welding,brazing, or other suitable means. A lining 21 of concrete or othersuitable material may be provided in which the fabric layer 19 isembedded. This lining 21 may be provided with reinforcement 22independently of the fabric layer 19.

Alternatively, the lining of concrete or other material may be providedWithout the prior provision of the inner fabric layer 19.

The ends of the pipes may be formed in any suitable or conventionalmanner to permit joining together; For example, one end of the core maybe enlarged to internal diameter greater than the outside diameter ofthe core and reinforcement so as to permit the ends of the pipes to betelescopically assembled.

Various methods of manufacture may be adopted. The outer fabric 12 maybe wrapped around the core under suitable tension and its edgesconnected by the rod 16 or the edges of the fabric may be firstconnected and the core then thrust into the tubeof fabric thus formed.Tn either of these methods, the fabric may be compressed in longitudinaldirection of the core, so as to render the operation easy and the fabricthen tensioned in the longitudinal direction of the core so as tocontract it circumferentially upon the core and thus obtain the desiredcircumferential tension. The fabric may be manufactured in seamlesstubular form and the core thrust into the fabric, the longitudinaltension being applied after or during insertion of the core. Thereinforcing fabric 12 may be applied to the empty core which may besupported on a mandrelor the core may be first lined with concrete, withor without the inner layer of fabric 19, so as to have stiffnesssufiicient to enable the outer fabric to be heavily tensioned thereon.

the fabric 12 may be formed Alternatively,

In'the formation of the around the core.

lining it is preferred if the nature of the -or other known or suitablemethod.

In the manufacture of columns, piles and the like according to theinvention, the process may be simllar in general to that alreadydescribed. In the columns or piles themselves, it is preferable that theconcrete filling extend be end the ends of the core or that suitable gtiments and caps fitting inside the core used so as to avoid placing thecore in longitudina compression, the function of the core and itsreinforcement being to resist burstin stresses in the concrete fillingwhen the lling is under longitudinal compression.

Pipes capable of withstanding high internal pressure without leaking maybe produced according to this invention if the reinforcing fabric isapplied under sufiicient tension and, in the case of a concrete linedpipe, after the lining is placed in the core.

Having thus described my invention, what disposed longitudinally of thecore and the I claim is 1. A composite pie, column and the likestructure subject to ursting stress comprising a thin-walled metal coreand an external metal reinforcin fabric tensioned around the core andrigidly attached to the core in: dependently of the tension of saidfabric, said reinforcin fabric being composed of a series of helica lyformed members disposed axiall lengthwise of'the structure, the heliceso adoining members being interlinked and constituting substantiallyinelastic binding elements extending circumferentially of the core, anda coverin of cementitious material entering into t e interstices of thefabric and being thereby retained even in the event of fracture,independently of any other reinforcement.

2. A structure according to claim 1, in which the reinforcing fabric istensioned circumferentially and longitudinally of the core.

,3. In combination with a structure accordthe outer reinforcinfabric,located within the core and dispose with the helical mem-.

bers thereof extending circumferentiall'y of the core, and a lining ofconcrete or other. suitable material in which the helices of the innerfabric are embedded.

6; In a structure subject to bursting stress,

' a thin-walled metal core and an external reinforcing fabricsurrounding the core and rigidly attached thereto and composed of aseries of helically formed members extending longitudinally of the core,the helices of said members being interlinked and constitutingsubstantially inelastic elements extending circumferentially of thecore, the

fabric being tensioned longitudinally and circumferentially of the core,a rigid lining within the core supporting the circumferential tension ofthe outer reinforcing fabric and an outer protective covering of rigidcementitious material engaging in the interstices of the fabric withcover retaining and fabric supporting efiect.

7. A structure including a thin-walled metal core, outer and innerlayers. of metal fabric in contact with the core and composed ofparallel helically formed members, the helices of each member beinginterlinked with the helices of the adjoining members, the helicalmembers of the outer layer being ric encircling the core, said fabricbeing com-' osed of a series of helically formed memers disposed axiallylengthwise of the structure, the helices of adjoining members beininterlinked and constituting core encircling elements adapted forengagement in a covering material ap lied in plastic state with coverretaining e ect upon said material when hard and adapted to besupported, by said covering material when hard, against flexion such aswould produce elongation of the encircling elements by pressure withinthe structure.

10. Incombination in a composite pipe, column and like structure subjectto bursting stress, a core, metal reinforcement for said core comprisinga senes of helically formed members disposed longitudinally of thestructure, the helices of adjoining members being interlinked andconstituting core encircling elements, said helices tending to bedistorted by pressure within the structure i ocfcimg mliollyoufiwmrfilly, smdl m covoxing of hard mmeriol in which tbho helices offiho ro= inforcemom; am embedidled with oovor remining efiecfu, .ssaidihelices beim the covering against dlistortlon as mforosmidl andoperating when subject to forces trendiing to cause dlsibortion asaforesaid, to exam inwardly acting pmssum on inho covering mmbariml"Within thomh In Witness whereof, I have hoyoamfixo sot my bond;

supporfosd Toy

